Montesquieu was fascinated by the liberty which was enjoyed in England, which he attributed to security of person and the rule of law (1748)

Montesquieu was fascinated by the liberty which was enjoyed in England, which he attributed to the sharp separation of political powers:

The political liberty of the subject is a tranquillity of mind arising from the opinion each person has of his safety. In order to have this liberty, it is requisite the government be so constituted as one man need not be afraid of another.
When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty; because apprehensions may arise, lest the same monarch or senate should enact tyrannical laws, to execute them in a tyrannical manner.

CHAP. VI.

Of the Constitution of England.

IN every government there are three sorts of power: the legislative; the executive in respect to things dependent on the law of nations; and the executive in regard to matters that depend on the civil law.

By virtue of the first, the prince or magistrate enacts temporary or perpetual laws, and amends or abrogates those that have been already enacted. By the second, he makes peace or war, sends or receives embassies, establishes the public security, and provides against invasions. By the third, he punishes criminals, or determines the disputes that arise between individuals. The latter we shall call the judiciary power, and the other, simply, the executive power of the state.

The political liberty of the subject is a tranquillity of mind arising from the opinion each person has of his safety. In order to have this liberty, it is requisite the government be so constituted as one man need not be afraid of another.

When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty; because apprehensions may arise, lest the same monarch or senate should enact tyrannical laws, to execute them in a tyrannical manner.

Again, there is no liberty if the judiciary power be not separated from the legislative and executive. Were it joined with the legislative, the life and liberty of the subject would be exposed to arbitrary controul; for the judge would be then the legislator. Were it joined to the executive power, the judge might behave with violence and oppression.

There would be an end of every thing, were the same man, or the same body, whether of the nobles or of the people, to exercise those three powers, that of enacting laws, that of executing the public resolutions, and of trying the causes of individuals.

About this Quotation:

For many 18th century Europeans there were two end points on the spectrum concerning liberty. On the far end was Turkey which embodied all that was bad about “oriental despotism”. Voltaire’s Philosophical Dictionary is full of references to the evils of the Turkish model. At the other end of the spectrum was the English constitution which was seen as the embodiment of measured and balanced government under which individuals could flourish. Things began to change after the American Revolution. European classical liberals were now torn between the American “republican” model of liberty and the British “constitutional monarchist” model.